Sex differences in in-hospital mortality and revascularisation among young adults with acute myocardial infarction: evidence of an ischaemic paradox from a national cohort (2018–2022)

Background Acute myocardial infarction (AMI) in adults aged 18–55 years presents ongoing challenges, with evidence indicating worse outcomes for young women compared to men. This study investigates sex differences in AMI outcomes, treatment, and comorbidity burden to explore the “ischaemic paradox” where women experience higher mortality despite similar or lower risk profiles. Methods A national inpatient cohort of young AMI discharges from 2018 to 2022 (N=602,565) was analyzed using survey weights to generate national estimates. Comparisons between men and women were made on in-hospital mortality, revascularisation rates (PCI and CABG), and comorbidity burden. Survey-weighted multivariable logistic regression adjusted for patient demographics, hospital characteristics, and Elixhauser comorbidities. Results Young AMI discharges were more frequent in men (2.12 million) than in women (0.89 million). Crude in-hospital mortality was similar by sex (men 2.04%, women 2.02%), but women had lower rates of PCI (42.12% vs 53.17%) and CABG (5.52% vs 7.94%). Adjusted analyses revealed female sex was associated with higher odds of in-hospital mortality (OR 1.134), slightly higher odds of PCI (OR 1.075), and lower odds of CABG (OR 0.817). Mortality peaked in 2020 for both sexes, with persistent lower revascularisation use in women. Conclusions Despite similar crude mortality, adjusted analyses confirm higher in-hospital mortality for young women with AMI, supporting the persistence of the ischaemic paradox. Differences in treatment utilization suggest sex-specific variations in case-mix and treatment selection. Further research incorporating detailed AMI phenotyping and treatment timing is needed to address sex disparities in outcomes.